Basel, Switzerland
Basel, Switzerland

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Durst H.-J.,Schluchseewerk AG | Brumann O.,Gruner AG | Grohmann P.,Greuter AG | Halter M.,Stahlton AG | Kesselring P.,Ingenieurburo Kesselring
WasserWirtschaft | Year: 2013

The weir Dogern (built in 1932) did not fulfil the stability criteria of the current Swiss standards. To increase the safety against sliding 10 to 11 prestressing rock anchors have been installed in each pillar. The Swiss-made anchors with corrosion-protection were unusually long: 72 m total length. A detailed quality assurance programme was necessary to ensure that every anchor would meet the quality requirements.


Privara S.,Czech Technical University | Privara S.,ETH Zurich | Vana Z.,Czech Technical University | Gyalistras D.,ETH Zurich | And 5 more authors.
Proceedings of the IEEE International Conference on Control Applications | Year: 2011

Predictive control in buildings has undergone an intensive research in the past years. Model identification plays a central role in a predictive control approach. This paper presents a comprehensive study of modeling of a large multi-zone office building. Many of the common methods used for modeling of the buildings, such as a detailed modeling of the physical properties, RC modeling, etc., appeared to be unfeasible because of the complexity of the problem. Moreover, most of the research papers dealing with this topic presents identification (and control) of either a single-zone building, or a single building sub-system. On contrary, we proposed a novel approach combining a detailed modeling by a building-design software with a black-box subspace identification. The uniqueness of the presented approach is not only in the size of the problem, but also in the way of getting the model and interconnecting several computational and simulation tools. © 2011 IEEE.


Privara S.,Czech Technical University | Cigler J.,Czech Technical University | Vana Z.,Czech Technical University | Oldewurtel F.,ETH Zurich | And 2 more authors.
Energy and Buildings | Year: 2013

Recent results show that a predictive building automation can be used to operate buildings in an energy and cost effective manner with only a small retrofitting requirements. In this approach, the dynamic models are of crucial importance. As industrial experience has shown, modeling is the most time-demanding and costly part of the automation process. Many papers devoted to this topic actually deal with modeling of building subsystems. Although some papers identify a building as a complex system, the provided models are usually simple two-zones models, or extremely detailed models resulting from the use of building simulation software packages. These are, however, not suitable for predictive control. The objective of this paper is to share the years-long experience of the authors in building modeling intended for predictive control of the building's climate. We provide an overview of identification methods for buildings and analyze their applicability for subsequent predictive control. Moreover, we propose a new methodology to obtain a model suitable for the use in a predictive control framework combining the building energy performance simulation tools and statistical identification. The procedure is based on the so-called co-simulation that has appeared recently as a feature of various building simulation software packages.


Schadler W.,WPW Geoconsult Sudwest GmbH | Borgatti L.,University of Bologna | Corsini A.,University of Modena and Reggio Emilia | Meier J.,Gruner AG | And 2 more authors.
Landslides | Year: 2015

This research proposes a conceptual approach for analysis and numerical modelling of the hydromechanical behaviour of large landslides, applied to one of the source areas of the Corvara earthflow (Dolomites, Italy). The approach consists of two steps: forward calculation and inverse analysis. For the forward calculations, the geological model of the slope considering several shear zones delimitating landslide units was developed, based on a detailed dataset of field investigation and monitoring data. A viscoplastic constitutive model was used to describe the time-dependent material behaviour, i.e. the creep, of the shear zones. The transient distribution of pore water pressure in the slope was considered by means of an additional purely hydrogeological model. These results were used as averaged hydraulic boundary conditions in the calculation of stress and deformation fields with the continuum finite element method (FEM). The numerical model was then calibrated against ground surface displacement rates measured by D-GPS, by iteratively varying the material parameters of the shear zones. For this task, an inverse analysis concept was applied, based on statistical analyses and an evolutionary optimisation algorithm. The inverse modelling strategy was further applied to gather statistical information on model behaviour, on the sensitivity of model parameters and on the quality of the obtained calibration. Results show that the calibrated model was able to appropriately simulate the displacement field of the earthflow and allow the requirements, difficulties and problems, as well as the advantages and benefits of the proposed numerical modelling concept to be highlighted. © 2014, Springer-Verlag Berlin Heidelberg.


Meier J.,Gruner AG | Moser M.,Friedrich - Alexander - University, Erlangen - Nuremberg | Datcheva M.,Bulgarian Academy of Science | Schanz T.,Ruhr University Bochum
Acta Geotechnica | Year: 2013

This paper deals with the inverse problem of using time-displacement monitoring data to determine the material parameters of a numerical model of a large-scale mass movement. A finite element model for simulating the mechanical behavior is presented for the Gradenbach landslide in Carinthia, Austria. Particular attention is paid to the calibration of the constitutive relationships, which represent a prerequisite for a realistic quantitative analysis. After a short introduction to the concept of model-parameter identification, this paper demonstrates how to apply the proposed model identification strategy to determine model parameters for the Gradenbach example. The impact of the amount of reference data available for the inverse model-parameter analysis is evaluated by means of artificial reference data. Subsequently, the numerical model is calibrated using field measurement data. The results obtained are presented, and the benefits and drawbacks of the proposed concept are evaluated. © 2013 Springer-Verlag Berlin Heidelberg.


Meier J.,Gruner AG | Bock H.,QS Consult
International Journal of Rock Mechanics and Mining Sciences | Year: 2014

Blocks of granitic rock, resting on inclined exfoliation planes, show evidence of a downward movement despite the fact that the friction angle of the contact planes is significantly higher than the inclination of the planes. In a pilot study an approximately 0.5m thick slab of rock with a volume of about 2.6m3 resting on a plane inclined by 22° was monitored on its displacement and temperature behaviour. The measurements revealed that the block is subject to distinct cyclic distortions due to temperature effects from solar radiation. The problem was modelled in 3-D by means of the finite element (FE) code Abaqus/Standard. It was possible to qualitatively reproduce the essential thermo-mechanical features of the rock block under consideration. It is shown that intermittent slip of discrete contact points at the base of the block is a key factor in the downward movement of the block. The shear strength of the contact points is sequentially exceeded due to cyclic reaction forces imposed by thermally-induced expansion/shortening and warping of the block. © 2014 Elsevier Ltd.


Major rail projects pose numerous challenges for design, construction, installation, commissioning and later operation. In order to be able to harmonise all these sometimes very varied subjects and activities, extensive consideration is necessary in advance. Increasing tunnel lengths, more stringent requirements for tunnel safety and also for the demands to exploit the available technology are reasons for the massive growth of technical equipment that has been observed. This trend must be followed very carefully and critically, particularly in order that it does not lead to any further increase of maintenance costs, reduction of the availability of the facilities or limitation of the capacity or quality of operations. These points are gaining ever higher priority through the newly opened railway lines (western line Vienna-St. Pölten - 60 km/Unterinntalbahn - 40 km) and the experience gained from them. On current and future projects, questions of rail fittings and equipment must therefore be considered as early as possible in order to be able to reduce the plant to a necessary minimum. © 2014 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.


Rodler J.,Gruner GmbH | Hagenah B.,Gruner GmbH | Lassy R.,Wiener Linien
BHR Group - 15th International Symposium on Aerodynamics, Ventilation and Fire in Tunnels 2013 | Year: 2013

Dust in railway tunnels / underground mainly results from friction processes and has a high content of metal. This becomes an increasing problem for operation because of its conductivity which endangers electrical components. Fine dust also can lead to health problems for the maintenance staff. In shops of station concourses, the fine dust pollutes displays and products. The effort on cleaning therefore is increasing as well in underground stations as in rail tunnels and cross-passages. Examples are presented to show specific situations and measures to improve the situation are illustrated. Investigations were undertaken in the Lotschberg base tunnel with the use of several measures to separate fine dust from the volume flow into the cross-passages. As this volume flow is needed to dissipate the lost heat generated by the equipment in the cross-passages, its prevention is not possible. This paper shows a useful possibility to overcome the problem. © BHR Group 2013.


Langner V.,Gruner GmbH | Hagenah B.,Gruner GmbH | Cronvall T.,VR Track Oy
BHR Group - 15th International Symposium on Aerodynamics, Ventilation and Fire in Tunnels 2013 | Year: 2013

The amount of frost is an important parameter for civil engineering projects in areas with dominant winters. The relevant measure for the amount of frost is the air freezing index (AFI). For tunnels, the AFI along the length of the tunnel can be determined with the help of 1D climate simulations. Aside from climate conditions and other aspects along with planning principles for cold climate boundary conditions in Finland, this article presents simulation results for a sample tunnel with different measures that can be applied to reduce ice formation in the portal regions and thus reduce the high costs of tunnel insulation. © BHR Group 2013.


Patent
Gruner AG | Date: 2015-11-17

A relay for closing or interrupting the electric circuit between two relay connection contacts includes two contact springs which are each fixed in an electrically conductive manner to the relay connection contacts with the spring ends thereof facing away from each other and which face each other with the other free, deflectable spring ends thereof. A stationary, electrically conductive contact bridge, against which the free spring ends abut in the closed relay position and from which the free spring ends are lifted in the open relay position, is included. A single solenoid-operated mechanism is for the synchronous, parallel deflection of the two contact springs into the closed or open relay position.

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